• Korean Journal of Food Science and Technology
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• v.28 no.1
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• pp.19-27
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• 1996

Zanthoxylum piperitum and Z. schinifolium have been utilized not only as food stuffs, but also as medicinal plants in Korea. In this study, lipids, sugar, amino acids and other components of Zanthoxylum piperitum and Z. schinifolium peels and seeds were analyzed by HPLC and GLC. Four samples contained common fatty acids such as linoleic, linolenic, palmitic, oleic and stearic acid. The contents of unsaturated fatty acids were 87.1% and 64.8% in Z. schinifolium peels and seeds, 73.6% and 62.9% in Z. piperitum peels and seeds, respectively. Z. schinifolium peels contained only beta-sitosterol, whereas other three samples contained campesterol, stigmasterol and beta-sitosterol. In case of free amino acids, peels of both species showed higher contents of acids than seeds of both species. Glutamic acid, aspartic acid, arginine, valine, and leucine were found in all four samples. Essential oils consisted of limonene (30.1-66.8%), beta-phellandrene (4.8-13.3%), citronellal (1.5-22%) and cineol (1.6-3.9%). It is worthwhile to note that the content of citronellal in Z. schinifolium seeds was higher than that of the others.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.21 no.4
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• pp.158-163
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• 2011

$CuInS_2$ thin films were prepared using a sol-gel spin-coating method. That makes large scale substrate coating, simple equipment, easy composition control available. The structural and optical properties of $CuInS_2$ thin films that include less toxic materials (S) instead of Se, tetragonal chalcopyrite structure. Copper acetate monohydrate ($Cu(CH_3COO)_2{\cdot}H2O$) and indium acetate ($In(CH_3COO)_3$) were dissolved into 2-propanol and l-propanol, respectively. The two solutions were mixed into a starting solution. The solution was dropped onto glass substrate, rotated at 3000 rpm, and dried at $300^{\circ}C$ for Cu-In as-grown films. The as-grown films were sulfurized inside a graphite container box and chalcopyrite phase of $CuInS_2$ was observed. To determine the optical properties measured optical transmittance of visible light region (380~770 nm) were less than 30 % in the overall. The XRD pattern shows that main peak was observed at Cu/In ratio 1.0 and its orientation was (112). As annealing temperature increases, the intensity of (112) plane increases. The unit cell constant are a = 5.5032 and c = 11.1064 $\AA$, and this was well matched with JCPDS card. The optical transmittance of visible region was below than 30 %.

• Journal of Microbiology and Biotechnology
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• v.14 no.6
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• pp.1200-1210
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• 2004

Metabolic flux analysis was established by adapting previous stoichiometric model developed during growth with cellulose to cell grown with cellobiose for further direct comparison of the bacterial metabolism. In carbon limitation with cellobiose, a shift from acetate-ethanol fermentation to ethanol-lactate fermentation is observed and the pyruvate overflow is much higher than with cellulose. In nitrogen limitation with cellobiose, the cellodextrin and exopolysaccharide overflows are much higher than on cellulose. In carbon and nitrogen saturation with cellobiose, the cellodextrin, exopolysaccharide, and free amino acids overflows reach the highest levels observed but all remain limited on cellulose. By completely shunting the cellulosome, the use of cellobiose allows to reach much higher carbon consumption rates which, in return, highlights the metabolic limitation of C. cellulolyticum. Therefore, the physical nature of the carbon source has a profound impact on the metabolism of C. cellulolyticum and most probably of other cellulolytic bacteria. For cellulolytic bacteria, the use of soluble carbon substrate must carefully be taken into consideration for the interpretation of results. Direct comparison of metabolic flux analysis from cellobiose and cellulose revealed the importance of cellulosome, phosphoglucomutase and pyruvate-ferredoxin oxidoreductase in the distribution of carbon flow in the central metabolism. In the light of these findings, future directions for improvement of cellulose catabolism by this bacterium are discussed.

• Journal of the Korean Wood Science and Technology
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• v.43 no.5
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• pp.591-599
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• 2015

Cercidiphyllum japonicum leaves were collected, air-dried and extracted with 70% aqueous acetone, then concentrated and sequentially fractionated using n-hexane, methylene chloride ($CH_2Cl_2$), ethylacetate (EtOAc), and $H_2O$. A portion of EtOAc fraction (10 g) was chromatographed on a Sephadex LH-20 column, by the successively elution with various aqueous $MeOH-H_2O$ (1:9, fraction $1-2{\rightarrow}3:7$, fraction $3-5{\rightarrow}1:1$, fraction $6-9{\rightarrow}7:3$, fraction $10-13{\rightarrow}9:1$, fraction 14-16). Compound 2 was isolated from fraction 6 and compound 1 was separated from fraction 11 and 12. Compound 3 and 4 were purified from fraction 13. The isolated compounds were elucidated as quercetin-3-O-${\alpha}$-L-rhamnopyranoside (1), chlorogenic acid (2), quercetin-3-O-${\alpha}$-L-arabinofuranoside (3) and quercetin-3-O-${\beta}$-D-xylopyranoside (4) by the spectral and literature data, and by comparison with the authentic samples. These compounds were reported, for the first time, from the extracts of C. japonicum leaves. Also chlorogenic acid (2) has never been reported before in domestic tree species and can be used as an index compound for C. japonicum.

• Food Science and Biotechnology
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• v.14 no.3
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• pp.344-349
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• 2005

Aldose reductase catalyzes the conversion of glucose into sorbitol. Inhibiting this enzyme in diabetes mellitus can delay or prevent pathogenic process. Aldose reductase inhibitor was screened from Korean fermented soybean pastes (Doen-jang) and purified via sequential processes of ethanol extraction, HP-20 column chromatography, ethyl acetate extraction, silica gel column chromatography, and crystallization. Aldose reductase inhibitor was identified as genistein with molecular weight of 270 Da and molecular formula of $C_{15}H_{10}O_5$ based on UV spectrometry, $^1H$ and $^{13}C\;NMRs$, and mass spectrometry. Genistein inhibited aldose reductase of pig lens with $IC_{50}$ level of $20\;{\mu}M$. Because genistein was effective against aldose reductase of animal source, it may be a potential therapeutic agent for diabetic complications.

• The Korean Journal of Food And Nutrition
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• v.34 no.5
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• pp.553-559
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• 2021

The aim of study to investigate the phytochemicals and biological activities the bark of Betula schmidtii. The studies consisted of the solvent extraction, followed by the isolation of phenolic components 1~3 from ethyl acetate-soluble fraction of Betula schmidtii Bark. Their chemical structures were identified as arbutin (1), ρ-coumaric acid (2) and ferulic acid (3) using Ultraviolet-Visible (UV-Vis) Spectrophotometer, Electrospray Ionization Mass Spectrometry (ESI-MS) (negative ion mode), ¹H-Nuclear Magnetic Resonance (NMR), ¹³C-NMR, ¹H-¹H Correlation Spectroscopy (COSY) and ¹H-¹³C Hetero Nuclear Multiple Quantum Correlation (HMQC) spectral data. Compounds 1~3 shows the anti-oxidant effect with IC₅₀ values of 29.74±1.52, 21.32±1.07 and 34.41±1.24 in 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity, respectively. Also, compounds 1~3 exhibited mushroom tyrosinase inhibitory activity with IC₅₀ values of 31.14±1.07, 42.54±1.46 and 69.22±1.43 µM, respectively.

• Korean Journal of Food Science and Technology
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• v.25 no.6
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• pp.677-682
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• 1993

Hexane(Hx), ethyl acetate(EtoAc) methanol(MeOH) and 99% ethanol(EtOH) extract of Rhus javanicus Lines with synergists e.g. ascorbic acid(AA), citric acid(CA) and ${\delta}-tocopherol$(TO) were tested their antioxidative effect on palm oil and lard by Rancimat. The methanol showed the highest extraction yield as 14.53%(w/w). When each 600 ppm of Hx, EtOAc, MeOH and EtOH extract with 200 ppm of AA was added to palm oil, the antioxidative index(AI: induction time of oil containing of each extract/induction time of test oil) were 1.83, 2.25, 2.81 and 2.85 respectively which were higher than other treatments and 600 ppm of each extract with 200 ppm of TO to lard, the AI were 3.64, 7.83, 7.34 and 9.30 respectively. Each solvent fractionate of EtOH and EtOAc extracts resulted no higher antioxidative effect than crude whole extract. Palm oil and lard containing 600 ppm of methanol extract were very stable comparing with the control by POV and TBA at oven test($60^{\circ}C$).

• Korean Journal of Weed Science
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• v.14 no.2
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• pp.81-93
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• 1994

This study was conducted to characterize herbicidal activity of the new type diphenylether compounds inducing bleaching(whitening) in relation to their chemical structures and to find out the herbicidal action mechanism. Bleaching was highly appeared in the compounds which have short chain alkyl or allyl group of cabamoyl type in meta position of A ring and nitro group in para position of B ring, and KC6361 showed the highest efficacy among these derivatives. Rice was tolerant to KC6361 at 2.0kg/ha. The applications of this compound at 0.25~1.0kg/ha provided acceptable control of the various weeds including large crabgrass, barnyardgrass, pigweed and so on. In the dark condition, KC6361 decreased carotenoid contents but increased chlorophyll in etiolated cucumber cotyledon. By the increase of light intensity, the carotenoid biosynthesis was more inhibited than the chlorophyll biosynthesis. The incorporation of $C^{14}$-acetate into lipid was slightly inhibited. Both KC6361 and norflurazon stimulated growth of dwarf rice(cv. Daneunbanju). These results suggest that both KC6361 and norflurazon may have the same action sites. To confirm this hypothesis, the changes of carotenoid intermediates in cucumber cotyledon and barnyardgrass leaf treated with KC6361 were investigated. Phytoene and phytofluene were increased but ${\beta}$-carotene was decreased, indicating that KC6361 inhibited phytoene and/or phytofluene dehydrogenase like norflurazon.

• Korean Journal of Food Science and Technology
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• v.38 no.3
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• pp.355-360
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• 2006

Antioxidative activity and physicochemical characteristics of heat-treated licorice extracted by ethyl-acetate (EtOAc) and ethyl-alcohol (EtOH) were evaluated at various treatment temperatures (110, 120, 130, 140, and $150^{\circ}C$), times (1, 2, 3, 4, and 5 hr), and moisture contents (10, 20, 30, 40, and 50%). Maximum extraction yields of EtOAc treated at $140^{\circ}C$, 2 hr, and 20% moisture content and EtOH extracts treated at $120^{\circ}C$, 2 hr, and 40% moisture content were 9.48 and 32.90%, whereas those of control were 3.74 and 14.60%, respectively. Highest total polyphenol content was obtained from 13.95 mg/g EtOH extract treated at $150^{\circ}C$, 3 hr, and 30% moisture content (control: 6.92 mg/g). Highest antioxidative activity $(IC_{50})$ was obtained from 0.32 g/L EtOAc treated at $140^{\circ}C$, 2 hr, and 20% moisture content (control: 0.57 g/L). Highest ascorbic acid equivalent antioxidant activity value of 2,112.61 mg ascorbic acid (AA) eq was obtained from EtOAc extract treated at $120^{\circ}C$, 2 hr, and 40% moisture content (control: 1,920.27 mg AA eq). Optimum heat treatment conditions were $130-140^{\circ}C$, 3 hr, and 30% moisture content.

• Journal of Food Hygiene and Safety
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• v.14 no.4
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• pp.358-364
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• 1999

Propolis, a natural resinous compound collected from honey bees, contains many biochemical constituents and has been used in traditional medicines as early as 300 B.C. Recently, it has been reported to possess many biological activities such as antibacterial, antiviral, fungicidal, local anaesthetic, immunostimulating, antiinflammatory and free radical scavenging properties. This study was performed to investigate the pharmacological effects of the propolis extract and fractions on the gastric lesion and ulcer. The ethanol extract was fractionated with hexane, toluene and ethyl acetate. Followed by bioassay on antigastric and antiulcer activity. Propolis ethanol extracts(500, 750, 1,000, 1,500 and 2,000 mg/kg) showed the protective effect on HCl·ethanol-induced gastric lesion and the antisecretory effect against Shay’s gastric secretion in pylorus-ligated rats in a dose related manner. In the animal models of HCl·ethanol, aspirin-induced gastric lesion and Shay’s gastric secretion, the hexane and toluene fraction of propolis significantly reduced the length of gastric lesion and the acid secretion. These data showed that the gastric protective effects of propolis might result from reduction of acid secretion through the inactivation of H+/K+ATPase activity.